Socket for led light source and lighting system using the socket

ABSTRACT

A socket fixed to a heat sink holds a card-type LED module formed by integrating LED elements. The socket ( 6 ) includes: a frame structure for holding the LED module ( 1000 ) with its light source unit exposed through the frame opening; and a pressing member positioned around the opening for pressing the back surface of the LED module against the heat sink ( 2122 ). The socket may include a structure including a lower member ( 61 ) placed on a heat sink and an upper frame member ( 62 ) holding the LED module with its light source unit ( 1002 ) exposed through the frame opening. The upper member supported by the lower member via a hinge can open/close, and includes a pressing unit pressing the LED module set in the open state, against the lower member ( 61 ). The lower member ( 61 ) includes, in its main part, a lock unit ( 63 ) directly or indirectly lock the upper member ( 62 ) when the upper member is closed.

TECHNICAL FIELD

The present invention relates to a socket designed for an LED lightsource for lighting applications, and in particular relates to a socketsuitable for a card-type LED module formed by mounting LED bare chips ona metal substrate, and to a lighting system using the socket.

BACKGROUND ART

LED (light emitting diode) light sources are now calling attentions asnext-generation new light sources. Unlike typical conventional lightsources, LEDs do not use a filament and therefore have a long life.Further, LEDs have a number of advantageous features such as compactmanufacturing due to its extremely small and thin dimensions. A widerange of lighting applications are expected for LEDs as light sources,with its favorable features including reduced limitations on themounting position.

As one example, Japanese Laid-Open Patent Application No. S62-8403discloses a lighting system that uses an LED light source formed byarranging linear lead frames in parallel, with each lead frame holding aplurality of through-hole type LED elements. Further, one technique isavailable for removably mounting such an LED light source as a“card-type LED module”. The “card-type LED module” is formed byarranging, instead of the lead wires, surface-mounting-type LED elementsin parallel on a card-type substrate. This technique enables, on a mainsubstrate where the socket is placed, various card-type LED modules eachdiffering in color and illuminance of emitted light to be selectivelymounted depending on the situation.

A card-type LED module formed by mounting a large number of LED barechips on a metal base substrate has recently been developed. Thiscard-type LED module is expected to have a higher illuminance by futureresearch and development efforts in improving the luminous efficiency ofLED bare chips, improving the packing density, and the like.

As one example, such a card-type LED module can be used as a lightsource for a lighting system by fixing the LED module to a lightingsystem 2000 using a socket 2020, according to a prior art techniqueshown in FIG. 16.

The lighting system 2000 shown in FIG. 16 is roughly composed of a base2001 to be screwed into a socket designed for general-purposeincandescent lamps, and a case 2002 on which a card-type LED module (LEDcard 1000) can be mounted.

The case 2002 has the socket 2020 for holding the LED card 1000, at itsbottom surface facing the surface where the base 2001 is attached.

The socket 2020 has grooves 2021 in which side parts 1000 a and 1000 bof the LED card 1000 can be engaged. The user mounts the LED card 1000by inserting the side parts 1000 a and 1000 b of the LED card 1000 intothe grooves 2021 of the socket 2020, and sliding the LED card 1000 fromthe peripheral part to the central part of the socket 2020. In lightingsystems, a light source is usually to be positioned at the center. Inthe lighting system 2000 with the above-described construction,therefore, the LED card 1000 is to be slid to a predetermined positionalong the grooves 2021 of the socket 2020, so that the LED card 1000 asits light source is positioned at the center.

The LED light sources for lighting applications will be required to havea higher illuminance in the future. To meet such a requirement, effortsare being made toward higher integration of LEDs and a larger drivingcurrent for the LEDs. These efforts are encountered with the followingproblem.

The higher integration and larger driving current can increase an amountof light emitted by an LED light source. In proportion to the increase,an amount of heat generated in the LED light source also increases. Itis generally recognized that an amount of heat generated in the LEDlight source is relatively small as compared with other typical lightsources, but an amount of heat generated in such a card-type LED havinga construction where a large number of LED elements are integrated isbeyond a negligible level. With serving as a light source for lightingapplications, LEDs included in the LED light source may be required tobe lit for long hours. The amount of heat generated in the LEDs isinevitably large. In particular, an illuminance of light emitted fromLEDs depends on their temperature characteristics. This means that someLEDs may fail to produce a desired illuminance under high-temperatureconditions. Also, a plurality of LEDs of different colors may havedifferent temperature characteristics. If these LEDs having differenttemperature characteristics are, combined for use as a light source,controlling of color emitted from the light source becomes difficult.

When a card-type LED module is inserted into a socket, heat generatedfrom each LED included in the card-type LED module is trapped in thevicinity of the socket. Such significant concentration of heat in onearea is problematic. In view of this, a card-type LED module is requiredto have good heat-releasing properties.

This requirement for good heat-releasing properties also applies to thelighting system 2000 shown in FIG. 16. To be specific, the LED card 1000is also required to have further improved heat-releasing properties whenthe socket 2020 described above is used.

Another problem to be solved is a difficulty in the replacementoperation of the LED card 1000.

To remove the LED card 1000 from the lighting system 2000 for suchreasons as its life being expired, the user is required to slide the LEDcard 1000 along the grooves 2021 from the central part toward theperipheral part of the case 2002. This removing operation can bedifficult for the user because the lighting system 2000 is often placedin an area of limited accessibility such as on the ceiling. Inparticular, if the user tries to remove the LED card 1000 byuncomfortable body positioning such as stretching his or her arms orbending his or her body, the side parts 1000 a and 1000 b of the LEDcard 1000 may get stuck in the grooves 2021, thereby increasing theburden on the user involved in the replacement operation. Accordingly,the lighting system 2000 needs to be improved to enable an easyreplacement operation of the LED card 1000.

In the lighting system 2000, a longer distance by which the LED card1000 is to be slid from the central part toward the peripheral part ofthe case 2002 not only makes the replacement operation difficult asdescribed above, but also degrades the appearance of the lightingsystem, with its construction being such that the grooves 2021 extendfrom the light source unit to the peripheral part of the case 2002.

To solve this problem, the lighting system may be constructed such thatthe socket 2020 is projected from the surface of the case 2002 so thatthe LED card 1000 can be placed at such a position that allows easyaccess by the user. In this case, however, the projected part maydrastically degrade the appearance of the lighting system. For thelighting system 2000, a recessed part may be formed in the surface ofthe case 2002, and the socket 2020 may be placed in the recessed part,so that the socket 2020 holding the LED card 1000 is not projected.However, simply employing such a constructing may further complicate thereplacement operation of the LED card 1000.

As described above, sockets designed for card-type LED modules forpractical use and lighting systems using the LED modules as lightsources still require improvements.

DISCLOSURE OF THE INVENTION

In view of the above problems, the object of the present invention is toprovide an LED light-source socket suitable for practical use thatenables stable driving while effectively releasing heat generated ineach LED during driving, and also to provide a lighting system havingthe socket without disfigurement of the lighting system.

The above object of the present invention can be achieved by a socketthat holds a card-type LED module and is fixed to a heat sink, the LEDmodule having a light source unit on a main surface thereof, the lightsource unit being formed by integrated LED elements, the socketincluding a frame structure that holds the LED module in a state wherethe light source unit is exposed through an opening of the framestructure, and that presses, at a position close to the opening, the LEDmodule to enable a back surface of the LED module to be pressed againsta surface of the heat sink.

According to this construction, the card-type LED module held by thesocket can also be pressed against the heat sink particularly at edgeparts of the light source unit. This ensures that the back surface ofthe LED module comes in contact with the heat sink. As a result of this,heat generated in the LED module is favorably conducted to the heatsink. Therefore, LEDs can be lit without increasing their temperatures.Accordingly, even LEDs having poor high temperature characteristics canproduce a high illuminance, thereby realizing stable driving of theLEDs.

Also, the frame structure may include a pressing member that haselasticity and is at such a position facing the LED module on a backsurface of the frame structure.

According to this construction, the LED module can come in directcontact with the heat sink in a state where the LED module is covered bythe socket. Therefore, a high heat-releasing effect can be produced.Further, the elastic pressing member provided in the socket securelypresses the LED module against the heat sink. Therefore, heat generatedin the LED module can be effectively released from the back surface ofthe LED module. In this case, a desired pressure can be obtained byadjusting the elasticity of the elastic pressing member.

Also, the pressing member may be formed integrally as a part of theframe structure.

By forming the elastic pressing member integrally as a part of the framestructure in this way, the number of components can be reduced, therebybeing advantageous in reducing the manufacturing cost.

Also, the frame structure may have a slot area through which the LEDmodule is removably inserted therein, and a cutout area that is formedto spatially connect the slot area and the opening, for guiding thelight source unit to the opening when the LED module is inserted.

According to this construction, the LED module can be easily mounted onand removed from the socket that has been fixed to the heat sink.Therefore, the socket provides practically high convenience.

Also, the frame structure may include a lower frame-part and an upperframe-part, the lower frame-part coming in contact with the heat sink,the upper frame-part being a frame for holding the LED module and beingfixed to the lower frame-part, and include a pressing member that haselasticity and is provided on the upper frame-part, and the pressingmember may press the LED module against a surface of the lowerframe-part, and the lower frame-part may be fixed in contact with thesurface of the heat sink.

According to this construction, the LED module is indirectly pressedagainst the heat sink via the lower member. Heat generated in the LEDmodule is still favorably conducted to the heat sink. As a result ofthis, a high heat-releasing effect can be produced. Further, the sockethaving this construction also has an advantage that the LED module canbe easily mounted on and removed from the socket even after the lowermember is fixed to the heat sink.

Here, the lower frame-part and the upper frame-part may be made of brassor stainless steel.

Also, a pressure applied by at least the pressing member to the LEDmodule may be in a range of0.05 to 1.00 kg/cm² inclusive. This rangecorresponds to pressures ranging from 0.3 to 6.7 kg applied to the LEDmodule overall. This range of pressures is determined by considering theoptimum pressing effect and the mechanical strength of the substrateused for the LED module.

Also, a feeding terminal may be provided at a position facing the LEDmodule on the frame structure, the feeding terminal may include aplurality of contacts made of phosphor bronze, and an elastic force ofthe contacts may press the LED module against the heat sink.

Also, the socket may be fixed to the heat sink via a screw. This methodis preferable because the LED module can be mounted on and removed fromthe socket relatively easily. Further, this method is advantageous inthat the pressure applied by the socket to the LED module can beadjusted by changing an amount by which the screw is screwed.

The above object of the present invention can also be achieved by asocket that holds a card-type LED module and is fixed to a heat sink,the LED module having a light source unit on a main surface thereof, theLED module being formed by integrated LED elements, the socket includinga frame structure including a lower frame-part and an upper frame-part,the lower frame-part being placed on the heat sink, the upper frame-partbeing a frame holding the LED module in a state where the light sourceunit is exposed through an opening of the frame, wherein the upperframe-part is supported by the lower frame-part via a hinge in such amanner that the upper frame-part can be open and closed, the upperframe-part includes a pressing unit for pressing the LED module againstthe lower frame-part, and the lower frame-part includes, in a main partthereof, a lock unit for directly or indirectly locking the upperframe-part when the upper frame-part is closed.

According to this construction, the LED module can be pressed againstthe lower member when the upper member is locked on the lower member bythe lock unit. Therefore, heat generated in the LED module can beeffectively released to the lower member or to the heat sink. Also, dueto the lock unit, the LED module can be easily removed simply by swayingthe upper member, thereby drastically improving the replacementoperability and the like, as compared with conventional cases. Further,a recessed part may be provided in the case in the lighting system andthe LED module may be placed within the recessed part. By doing so, theLED module can be mounted on or removed from the socket by swaying theupper member, without requiring a case to be projected from the heatsink. Accordingly, the lighting system with high operability andbeautiful finish can be realized.

Here, the upper frame-part may include a base part and a pair of armparts, the base part being supported on an axis in an area where theupper frame-part is supported by the lower frame-part, the pair of armparts respectively extending from both ends of the base part, the armparts may have grooves formed at facing positions thereof, for guidingedge parts of the LED module in a longitudinal direction of the armparts, and the pressing unit of the upper frame-part may be formedwithin the grooves to press the edge parts of the LED module against thelower frame-part in a state where the LED module is held in the grooves.

Further, an opening may be formed in the main part of the lowerframe-part for enabling a base surface of the LED module to face theheat sink.

According to this construction, the LED module and the heat sink candirectly face each other. Therefore, the heat-releasing effect can beimproved further.

Here, the lock unit in the main part of the lower frame-part may have aslide part placed to be slidable in a longitudinal direction of the armparts when the upper frame-part is closed, and the slide part may lockedges of the LED module held by the arm parts when the upper frame-partis closed, thereby the upper frame-part is indirectly locked.

Alternatively, the lock unit may be supported on an axis in a freelyswayable manner, at a position opposite to a position of the hingebetween the lower frame-part and the upper frame-part, and the lock unitmay sway toward the upper frame-part when the upper frame-part isclosed, thereby the upper frame-part is directly locked on the lowerframe-part.

By operating the lock unit with the sliding method or with the swayingmethod in this way, the LED module can be easily and securely mounted onand removed from the socket.

Also, the lower frame-part may have, in the main part, a projection foraligning the LED module.

By using the alignment projection in this way, the LED module can bedirectly mounted within the lower member at the time of replacement ofthe LED module, thereby further improving the replacement operability.

Also, the pressing unit may be formed integrally as a part of the upperframe-part by processing the part of the upper frame-part.

By forming the pressing member integrally as a part of the upper memberin this way, the number of components can be reduced, thereby beingadvantageous in reducing the manufacturing cost.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, advantages and features of the invention willbecome apparent from the following description thereof taken inconjunction with the accompanying drawings that illustrate a specificembodiment of the invention. In the drawings:

FIG. 1 shows the construction of an LED light-source socket relating toa first embodiment of the present invention;

FIG. 2 shows a back side of the socket relating to the first embodiment;

FIG. 3 shows a cross sectional view of the socket, for explaining theeffect of the present invention;

FIG. .4 shows the construction of an LED light-source socket relating toa second embodiment of the present invention;

FIG. 5 shows the construction of an LED light-source socket relating toa third embodiment of the present invention;

FIG. 6 shows the construction of an LED light-source socket relating toa fourth embodiment of the present invention;

FIG. 7 shows the construction of an LED light-source socket relating toa fifth embodiment of the present invention;

FIG. 8 shows a perspective view of the construction of a lighting systemrelating to a sixth embodiment of the present invention;

FIG. 9 shows the construction of an LED light-source socket relating tothe sixth embodiment;

FIG. 10 shows a side cross sectional view of the construction of thesocket relating to the sixth embodiment;

FIG. 11 shows the construction of an LED light-source socket relating toa seventh embodiment of the present invention;

FIG. 12 shows the construction of an LED light-source socket relating toan eighth embodiment of the present invention;

FIGS. 13A to 13C show side cross sectional views of the construction ofthe socket relating to the eighth embodiment;

FIG. 14 shows the construction of an LED light-source socket relating toa ninth embodiment of the present invention;

FIGS. 15A to 15C show the construction of a card-type LED module (LEDcard); and

FIG. 16 shows a perspective view of a conventional lighting system.

BEST MODE FOR CARRYING OUT THE INVENTION 1. FIRST EMBODIMENT

1.1 Construction of the Socket for LED Light Source

FIG. 1 shows the construction of a socket 1 designed for an LED lightsource, relating to a first embodiment of the present invention. FIG. 2shows the construction of a back side of the socket 1. FIGS. 15A to 15Cshow the construction of an LED card.

FIG. 1 shows the constructions of the socket 1 designed for an LED lightsource, a card-type LED module 1000 as one example of the LED lightsource (hereafter simply “LED card 1000”), and a heat sink 3000.

As shown in the figure, the heat sink 3000 is made from a rectangularsolid metal member (here, aluminum member) with good heat-releasingproperties. In one main surface of the heat sink 3000, a large number offins 3002 are formed like the teeth of a comb, to enhance theheat-releasing effect. On another main surface 3001 of the heat sink3000 (the upper surface in the figure), screw holes 3010 to 3013 (3013not shown) for screws 3100 to 3103 used to fix the socket 1 are formed.The LED card 1000 is placed on the main surface 3001 of the heat sink3000 so as to be positioned in its middle area surrounded by the screwholes 3010 to 3013.

The LED card 1000 includes a metal base substrate 1003 with goodheat-releasing properties (for example, with dimensions of 28.5 mm(length)*23.5 mm (width)*1.2 mm (thickness)). The metal base substrate1003 is formed by laminating a mount layer 1032 and a metal layer 1031.The mount layer 1032 has a light source unit 1002 and feeding terminals1001 a to 1001 n mounted thereon, and has a thickness of 0.2 mm. Themetal layer 1031 is made of aluminum or the like, and has a thickness of1.0 mm. the metal layer 1031 is provided for the purpose of enhancingthe heat-releasing effect.

The following describes a detailed construction of the LED card 1000. Asa cross sectional view of the LED card 1000 is shown in FIG. 15B, thelight source unit 1002 includes an 8 by 8 matrix of 64 LED elements 1010and an aluminum reflector plate 1020. Each LED bare chip 1013 iscontained in a semi spherical resin lens with a diameter of 2 mm. Thelens containing each LED bare chip 1013 is partially embedded in thealuminum reflector plate 1020 in such a manner that a gradient surfaceis formed to surround the LED element 1010. As shown in FIGS. 15C and15D, a phosphor and resin 1012 is coated on each LED bare chip 1013, anda silicone resin or an epoxy resin is filled on the phosphor+resincoating to form a resin lens 1011 (a detailed construction of the LEDcard 1000 is described in Japanese Laid-Open Patent Application No.2003-124528). It should be noted here that the mount layer 1032 is widerthan the light source unit 1002, and that margins are left around thelight source unit 1002. The LED elements 1010 are arranged appropriatelyin such a manner that some are in series and others are in parallel, andare electrically connected to the feeding terminals 1001 a to 1001 n.The feeding terminals 1001 a to 1001 n are respectively connected toelastic contact units 162 a to 162 n of an external terminal 16 of thesocket 1.

As shown in FIGS. 1 and 2, the socket 1 is composed of a frame member10, the external terminal 16, and the like. The frame member 10 is amain body of the socket 1, and is made of a stainless steel plate with athickness of 0.1 to 0.5 mm, which has good heat-releasing properties.The stainless steel plate is specifically subjected to such processingas pressing, bending, and cutting, to be shaped into the frame member.The frame member 10 has a main surface 11 in which an opening unit 110is formed to fit for the size of the light source unit 1002 of the LEDcard 1000, fixing legs 12R and 12L, and a leg 13. The fixing legs 12Rand 12L and the leg 13 are formed by cutting the corresponding parts ofthe stainless steel plate and bending the cut parts at the edges of themain surface 11 at substantially right angles. The fixing legs 12R and12L have their edge parts further bent to be in parallel with the mainsurface 11. Screw holes 120R, 121R, 120L, and 121L are formed in theedge parts of the fixing legs 12R and 12L. It should be noted here thatparts of the stainless steel plate corresponding to the edge vicinitiesof the opening unit 110 are also subjected to such processing as bendingand cutting, which is described later. A material for the frame member10 may be brass with good heat-releasing properties instead of stainlesssteel.

As shown in FIG. 2, three elastic pressing units 14R, 14L, and 14C areformed at inner edges of the rectangular opening unit 110 of the socket1. The elastic pressing units 14R, 14L, and 14C are blade springstructures formed integrally as parts of the frame member 10. At theinner edges of the opening unit 110, the elastic pressing units 14R,14L, and 14C are formed by punching the corresponding parts of thestainless steel plate into T-shaped parts and bending the T-shapedparts. The resulting elastic pressing units 14R, 14L, and 14Cspecifically have such a construction where bars 140R, 140L, and 140Csupport bars 141R, 141L, and 141C (141L not shown) whose both ends areprocessed to form arch shaped pressing contact units 142R, 143R, 142L,143L, 142C, and 143C. As described in detail later, the socket 1 isformed in such a manner that its height in the thickness direction is alittle smaller than the total of the height of the elastic pressingunits 14R, 14L, and 14C and the height of the LED card 1000 in thethickness direction, to securely press the LED card 1000 against themain surface 3001 of the heat sink 3000 by the elastic pressing units14R, 14L, and 14C.

On the back surface of the socket 1, a feeding terminal unit 15 isprovided along one side of the opening unit 110, at such positionscorresponding to the feeding terminals 1001 a to 1001 n of the LED card1000. The feeding terminal unit 15 has a construction where a terminalholding member 150 (an insulating housing) made of a resin material,such as liquid crystal polymer and a heat resistant and flame retardantmaterial, supports the external terminal 16. The external terminal 16 ismade of phosphor bronze having high electric conductivity and highdurability against insertion and removal operations. The feedingterminal unit 15 has elastic contact units 162 a to 162 n projected inthe direction where the opening unit 110 is positioned. The elasticcontact units 162 a to 162 n are warped in the thickness direction ofthe socket 1. Together with the elastic pressing units 14R, 14L, and14C, the elastic contact units 162 a to 162 n produce the effect ofpressing the LED card 1000 against the heat sink 3000. The elasticcontact units 162 a to 162 n are electrically connected to the externalterminal 16 of the LED card 1000. External contact units 161 a to 161 nof the feeding terminal unit 15 are projected externally from the socket1, and receive power supply from an external power source. To be morespecific, the external contact units 161 a to 161 n are connected to awell-known LED lighting circuit via a connector (not shown), aresupplied with power, and are driven accordingly.

The LED card 1000 can be removed and replaced easily by removing thescrews 3100 to 3103 as shown in FIG. 1. Here, the fixing of the socket 1and the heat sink 3000 may not necessarily be realized by using thescrews 3100 to 3103, but may be realized by other methods (e.g., usingpairs of hooks and tabs). Also, the heat sink 3000 may not necessarilybe rectangular, but may be in other shapes as long as the heat sink 3000has a flat surface with less warping and projections and recessions, toat least allow the back surface of the LED card 1000 to entirely come incontact with the surface of the heat sink 3000.

1-2. Effect of the LED Light-Source Socket

According to the above-described construction of the socket 1, the LEDcard 1000 can be placed within the socket 1 with its light source unit1002 being exposed through the opening unit 110, and with being fixed bythe fixing legs 12R and 12L and the leg 13 of the socket 1, and beingfixed, together with the socket 1, to the heat sink 3000 via the screws3100 to 3103 screwed into the screw holes 120R, 121R, 120L, and 121L.

Here, the LED card 1000 comes in contact with the pressing contact units142R, 143R, 142L, 143L, 142C, and 143C, and the elastic contact units162 a to 162 n. Due to the elastic force of the three elastic pressingunits 14R, 14L, and 14C and the elastic contact units 162 a to 162 n ofthe external terminal 16, the LED card 1000 is securely pressed againstthe main surface 3001 of the heat sink 3000. Here, the LED card 1000 isfixed, with receiving pressures applied by the three elastic pressingunits 14R, 14L, and 14C, and the elastic contact units 162 a to 162 n ina range of 0.3 to 6.7 kg to the LED card 1000 overall, i.e., in a rangeof about 0.05 to 1.00 kg/cm² inclusive. This range of pressures isdetermined by considering the optimum pressing effect and the mechanicalstrength of the substrate used for the LED card 1000. Due to this, theback surface of the LED card 1000 where the metal layer 1031 is formedfavorably comes into contact with the heat sink 3000.

As a cross sectional view of the LED card is shown in FIG. 3, thecontact between the LED card 1000 and the heat sink 3000 enablesgenerated heat to be conducted through the entire back surface of theLED card 1000 to the heat sink 3000. For lighting applications, the LEDcard 1000 is required to produce a high illuminance as compared with acase where the LED card 1000 is simply lit for use in displays etc. Forexample, each LED element 1010 is supplied with a relatively largecurrent of about 40 mA, and therefore, heat generated along with thesupply current often causes problems. The first embodiment of thepresent invention however can produce an extremely high heat-releasingeffect, and therefore enables stable driving and lighting of the LEDs.The luminous efficiency of LEDs tends to be lowered as the temperatureincreases. Therefore, the heat releasing effect produced by the firstembodiment enables a plurality of densely packaged LED elements toexhibit favorable luminous efficiency. This is extremely advantageouswhen LEDs with poor high-temperature characteristics are used forlighting applications.

An LED light-source socket is typically required to have a relativelylarge opening unit 110, to enable the light source unit 1002 of the LEDcard 1000 to be exposed through the opening unit. It is thereforebasically difficult to provide the LED light-source socket with suchmeans of pressing the LED card 1000 to the heat sink 3000. The firstembodiment of the present invention however solves this problem byforming the elastic pressing units 14R, 14L, and 14C in the edgevicinities of the opening unit 110 by such processing as bending andcutting.

Further, according to the first embodiment, as well as second and thirdembodiments of the present invention described later, the sockets 1 to 3are each fixed to the heat sink 3000 via screws. By adjusting an amountby which the screws are screwed into the holes, a degree of contactbetween the LED card 1000 and the heat sink 3000 can be adjusted.

2. SECOND EMBODIMENT

FIG. 4 shows the construction of an LED light-source socket relating toa second embodiment of the present invention.

The socket 2 relating to the second embodiment shown in the figure is,as its characteristic, formed by processing an aluminum plate with highheat conductivity. The socket 2 has a construction where an externalterminal unit 27 having the same construction as that in the firstembodiment is attached to a frame member 21 in which an opening unit 201is formed by punching or shaving off the corresponding part of thealuminum plate. The lower surface of the frame member 21 is subjected tosuch patterning to form steps that correspond to the shape of the LEDcard 1000, so that the LED card 1000 can be securely covered and held bythe frame member 21. The second embodiment differs from the firstembodiment in that the frame member 21 of the socket 2 presses theperipheral parts of the light source unit 1002. It should be noted herethat a heat sink with the same construction as the heat sink 3000 can beused in the present embodiment.

According to the above-described construction of the socket 2, the LEDcard 1000 can be placed right below the frame member 21. Using screwholes 220 to 250 formed in projected parts 22 to 25 of the frame member21 shown in the figure, the LED card 1000 can be fixed to the heat sink.Here, the light source unit 1002 of the LED card 1000 is exposed throughthe opening unit 201, with its peripheral parts being pressed in thedirection of the main surface 3001 of the heat sink 3000 by the framemember 21. Therefore, the back surface of the LED card 1000 and the mainsurface 3001 of the heat sink 3000 favorably come in contact. As aresult of this, the socket 2 can produce a high heat-releasing effect asthe effect described in the first embodiment.

3. THIRD EMBODIMENT

FIG. 5 shows the construction of an LED light-source socket relating toa third embodiment of the present invention.

As shown in the figure, the shape of the socket of the present inventionshould not be limited to the rectangular shape employed in the first andsecond embodiments. The socket 3 relating to the third embodiment iscomposed of a circular frame member 31 in which an opening unit 301 isformed. Screw holes 301 to 303 are formed in the frame member 31.

The socket 3 having this construction relating to the third embodimentcan produce substantially the same effect as the effect described in thesecond embodiment. To be specific, the LED card 1000 can be positionedright below the frame member 31. Using the screw holes 301 to 303 shownin the figure, the socket 3 in which the LED card 1000 is set can befixed to the heat sink. Here, the light source unit 1002 of the LED card1000 is exposed through the opening unit 201, with its peripheral partsbeing pressed in the direction of the main surface 3001 of the heat sink3000 by the frame member 31. Therefore, the back surface of the LED card1000 and the main surface 3001 of the heat sink 3000 favorably come incontact. As a result of this, the socket 3 can produce a highheat-releasing effect while securely holding the LED card 1000.

4. FOURTH EMBODIMENT

4-1. Construction of the Socket 4

FIG. 6 shows the construction of an LED light-source socket relating toa fourth embodiment of the present invention.

The socket 4 shown in the figure has, in addition to the effectdescribed in the first to third embodiments, an advantage of enablingextremely easy mounting and removing of the LED card 1000.

The socket 4 has a construction composed of an upper member 41 and alower member 42 each of which is formed by subjecting a stainless steelplate to such processing as punching and bending. The upper member 41and the lower member 42 are combined to form a space between them.

The upper member 41 is a rectangular frame member in which a rectangularopening unit 43 is formed. The rectangular frame member however has, onits entire one side, a cutout area that spatially connects the openingunit 43 and the outside of the socket 4 (in other words, one side of therectangular frame member is missing). The cutout area has the functionof guiding the light source unit 1002 of the LED card 1000, and alsoserves as a slot area through which the LED card 1000 is inserted intothe space between the upper member 41 and the lower member 42.

A plurality of hooks 411L, 412L, 413L, 414L, 411R, 412R, 413R, and 414R(411R, . . . not shown) are formed in edge parts of the upper member 41.

The lower member 42 is a plate member, and has, at its edge parts on itsmain surface, hooks 422L, 423L, 424L, 425L, 422R, 423R, 424R, and 425R(422R, . . . not shown) formed by cutting and bending the correspondingparts of the plate member.

As shown in FIG. 6, the upper member 41 and the lower member 42 arefixed together by combining these hooks 411L etc., and 422L etc. Acertain space is provided between the upper member 41 and the lowermember 42. In the fourth embodiment, the LED card 1000 is inserted inthis space formed between the upper member 41 and the lower member 42.

On the back surface of the upper member 41, elastic contact units 451Rand 451L and elastic contact units 442R and 442L (442L not shown)supported by elastic contact units 45R and 45L and bars 44R and 44L (44Lnot shown) are formed at two sides of the opening unit 43 of the uppermember 41, and terminals of an external terminal unit 46 are formed atone side of the opening unit 43 of the upper member 41.

The elastic contact units 45R etc. produce the effect of pressing theLED card 1000 placed between the upper member 41 and the lower member42, to enable the back surface of the LED card 1000 to come in contactwith the main surface of the lower member 42.

Further, screw holes 420L, 421L, 420R, and 421R (420R and 421R notshown) are formed in the lower member 42. The lower member 42 can befixed in contact with the main surface 3001 of the heat sink 3000 by thescrews 3100 to 3103.

4.2 Effect of the Socket 4

According to the above-construction of the socket 4, the LED card 1000can be inserted through the cutout area of the upper member 41 aroundwhich the elastic contact units 45R and 45L are provided, into the spacebetween the upper member 41 and the lower member 42. When the LED card1000 is inserted, the back surface of the LED card 1000 can be pressedagainst the surface of the lower member 42 by the elastic contact units45R etc. In this way, the LED card 1000 can be securely held within thesocket 4 without being dropped from the socket 4.

Here, by fixing the lower member 42 in contact with the heat sink 3000or the like, heat generated in the LED card 1000 can be efficientlyreleased from the heat sink via the lower member 42. In this way, thesocket 4 can produce the same high heat-releasing effect as the effectdescribed in the first to third embodiments.

In addition to this effect, the socket 4 relating to the fourthembodiment has an advantage due to its characteristic that the uppermember 41 has, on its entire one side, a cutout area spatiallyconnecting the opening unit 43 and the outside of the socket 4 unlike inthe first to third embodiments. Due to this characteristic, the socket 4has the advantage of enabling easy mounting and removing, andreplacement of the LED card 1000 even after the socket 4 is fixed to theheat sink 3000 by the screws 3100 to 3103.

To enable favorably easy mounting and removing of the LED 1000 in thefourth embodiment, pressures applied by the elastic contact units 44R,45R, 44L, and 45L need to be controlled so as not to be too high.

5. FIFTH EMBODIMENT

FIG. 7 shows the construction of an LED light-source socket relating toa fifth embodiment of the present invention.

Although the fourth embodiment describes, as one example, a constructionwhere the lower member 42 and the upper member 41 are combined, the LEDlight-source socket of the present invention should not be limited tothis construction. For example, as shown in FIG. 7, the socket 5relating to the fifth embodiment does not have a lower member, but ischaracterized by its relatively simple construction composed of an uppermember 41 alone. Screw holes 520R, 521R, 520L, 521L, etc., are formed inedge parts of the upper member 41. The construction of the socket 5 issubstantially the same as that of the socket 4 relating to the fourthembodiment except that the screw holes 520R, 521R, 520L, and 521L areformed in the edge parts of the upper member 41.

The socket 5 having this construction is fixed to the heat sink 3000 orthe like using the screw holes 520R, 521R, 520L, and 521L. The LED card1000 is inserted through a cutout area of the upper member 41 spatiallyconnecting the opening unit 43 and the outside, into a space formedbetween the upper member 41 and the heat sink. Here, the LED card 1000is pressed, in direct contact, against the heat sink (not shown) by theelastic contact units 45R etc. In this way, the LED card 1000 issecurely held by the socket 5 without being dropped from the socket 5.At the same time, heat generated in the LED card 1000 can be directlyreleased to the heat sink. The socket 5 relating to the fifth embodimenttherefore can produce a higher heat-releasing effect than the socket 4relating to the fourth embodiment.

6. SIXTH EMBODIMENT

6.1 Overall Construction of the Lighting System

FIG. 8 shows a perspective view of the construction of a lighting system2500 relating to a sixth embodiment of the present invention. Thelighting system 2500 uses the LED card 1000 as its LED light source.FIG. 9 shows the construction of a socket 6 relating to the sixthembodiment for an LED light source. FIG. 10 shows a cross sectional viewof the socket 6.

As shown in FIG. 8, the lighting system 2500 includes a base 2001, acase 2102, and the socket 6. The LED card 1000, which is a light source,can be set in the socket 6 in a replaceable manner.

The base 2001 employs the same specifications as those employed bytypical incandescent lamps. The base 2001 supplies alternating current,which is supplied from an external commercial power source, to a powersource circuit (not shown) of the case 2102.

The case 2102 has a tapering-off cylindrical shape, which is like ashape of a cone whose top part is cut off. The base 2001 is attached tothe top surface of the case 2102, and a plate-shaped heat sink 2122 isprovided on the bottom surface of the case 2102. Within the case 2102, awell-known power source circuit (not shown) is placed for convertingalternating current supplied from the base 2001 to direct current andsupplying the direct current to the socket 6.

As shown in FIG. 8, the heat sink 2122 has a rectangular recessed part2200 at the center of its main surface. The socket 6 relating to thesixth embodiment is fixed within the recessed part 2200 via screws 2300.It is preferable to form the recessed part 2200 to have such a depththat does not allow the socket 6 to be projected from the surface of theheat sink 2122.

By the swaying operation described later, the LED card 1000 is set, in afreely removable manner, in the socket 6 fixed within the recessed part2200. A cover 2400, which has a rectangular frame shape whose one sideis missing, is then placed within the recessed part 2200, to cover theLED card 1000 in a state where the light source unit of the LED card1000 is exposed. Due to the presence of the recessed part 2200 and thecover 2400, a substantially flat surface is formed with respect to themain surface of the heat sink 2122, around the periphery of the socket6. Therefore, the lighting system 2500 relating to the sixth embodimentcan have a beautiful finish without any disfigurement, compared forexample with the conventional lighting system 2000 shown in FIG. 16. Thegood appearance of the lighting system 2500 can be realized in this way,with the use of the socket 6 whose construction is described below.

6-2. Construction of the Socket 6

As shown in FIG. 9, the socket 6 relating to the sixth embodiment isformed by combining a lower member 61 and an upper member 62 via ahinge. With the construction described below, the socket 6 bases itsoperation on the swinging motion.

The lower member 61 includes a lower member main unit 610 that is arectangular plate made for example from a nickel-plated brass substratewith high heat conductivity. In one of the two shorter sides of thelower member main unit 610, a pair of lock supporting parts 611 isformed at facing positions. In the other one of the two shorter sides ofthe lower member main unit 610, a pair of upper member supporting parts612 is formed at facing positions. The lock supporting parts 611 and theupper member supporting parts 612 are formed by cutting and bending thecorresponding parts of the lower member main unit 610.

The lock supporting parts 611 are rectangular parts formed by cuttingthe corresponding parts of the lower member main unit 610 and bendingthe cut parts so as to be perpendicular to the main surface of the lowermember main unit 610. The two lock supporting parts 611 are positionedsymmetric to each other with a certain distance between them. In the twolock supporting part 611 respectively, guide openings 611 a and 611 b(611 b not shown) that extend parallel to the main surface of the lowermember main unit 610 are formed. A slide plate 630 is set on the locksupporting parts 611, to form a lock unit 63.

As shown in FIG. 9, the slide plate 630 has such a shape where twoshorter sides and one longer side of a rectangular plate are bent in theperpendicular direction. The slide plate 630 has projections 631 a and631 b formed respectively in the two shorter sides. The tips of theprojections 631 a and 631 b are placed in the guide openings 611 a and611 b. Due to this, the slide plate 630 is supported by the lower membermain unit 610 in a freely slidable manner. With the sliding motion ofthe slide plate 630, the lock unit 63 can partially cover an edge part1000 c of the LED card 1000 set between arm parts 620 b of the uppermember 62, thereby indirectly locking the upper member 62. Here, theslide plate 630, with its height being appropriately set, can securelyhold the LED card 1000 while appropriately pressing the LED card 1000against the lower member 61.

Like the lock supporting parts 611, the upper member supporting parts612 are also rectangular parts formed by cutting the corresponding partsof the lower member main unit 610 and bending the cut parts so as to beperpendicular to the main surface of the lower member main unit 610. Thetwo upper member supporting parts 612 are positioned symmetric to eachother with a certain distance between them. The upper member supportingparts 612 have a hinge axis 62 a placed to extend in the direction of ashorter side of the lower member 61. On the hinge axis 62 a, the uppermember 62 can freely swing open and close.

In the sixth to ninth embodiments, for the swing-type LED light-sourcesocket of the present invention, the state where the upper member swingson the hinge axis away from the lower member is referred to as “an openstate”, and the state where the upper member is directly or indirectlylocked on the lower member is referred to as “a closed state”.

It should be noted here that a heat-releasing sheet 613 is placed in apredetermined area of the main surface of the lower member main unit 610(at the central area in the example of FIG. 9). The heat-releasing sheet613 is placed in such an area corresponding to the area where the LEDcard 1000 held by the upper member 62 is to be positioned. Theheat-releasing sheet 613 comes in contact with the back surface of theLED card 1000, so that heat generated in the LED card 1000 can bereleased to the heat sink 2122 via the lower member 61.

Also, a plurality of screw holes 610 a are formed in edge parts of thelower member main unit 610, to fix the lower member main unit 610 to theheat sink 2122 shown in FIG. 8 via screws.

The upper member 62 has a rectangular frame shape whose one side ismissing, and is made from a member with a rectangular cross sectionwhose one side to be positioned at the inside of the frame opening ofthe upper member 62 is missing. To be more specific, the upper member 62includes a base part 620 a and a pair of arm parts 620 b extendingrespectively from both ends of the base part 620 a in one direction. Theupper member 62 has substantially the same size as the lower member 61overall, and is formed to be in a rectangular shape whose one shorterside is cut off, with two longer sides of the rectangular shapecorresponding to the arm parts 620 b and the remaining shorter side ofthe rectangular shape corresponding to the base part 620 a. An areasurrounded by the two arm parts 620 b and the base part 620 acorresponds to an opening unit 600. The LED card 1000 is set between thearm parts 620 b in a state where the light source unit 1002 is exposedthrough the opening unit 600.

Both ends of the base part 620 a in its longitudinal direction aresupported, on the hinge axis 62 a, by the upper member supporting parts612 of the lower member 61. In this way, the upper member 62 and thelower member 61 are combined together via the hinge. Inside the basepart 620 a, an external terminal unit 622 having the same constructionas that described in the first to fifth embodiments is provided. To bemore specific, the external terminal unit 622 includes a plurality ofrectangular external terminals 622 a to 622 n and a terminal supportingmember 622 b. The external terminals 622 a to 622 n are to beelectrically connected to feeding terminals 1001 a to 1001 n of the LEDcard 1000. The terminal supporting member 622 b is made of insulatingresin, and fixes the external terminals 622 a to 622 n, which arearranged in parallel, to the base part 620 a.

As shown in FIG. 9, the arm parts 620 b are formed to have a rectangularcross section whose one side is missing, and are placed so as to besymmetric to each other. The arm parts 620 b having such cross sectionsserve as guide grooves for the LED card 1000, and also form a slot areathrough which the LED card 1000 is inserted. The LED card 1000 is guidedthrough the guide grooves and set between the arm parts 620 b. Withineach arm part 620 b, an elastic contact unit 621 is formed. The elasticcontact units 621 are formed integrally as parts of the upper member 62.As shown in FIG. 9, the elastic contact units 621 are formed by cuttingthe corresponding parts of the plate used for the arm parts 620 b into Tshapes, and bending the T-shaped parts to form blade springs.

Further, at the tip of each arm part 620 b, an elastic contact unit 620c is formed by folding a tip part of the arm part 620 b inward. Theelastic contact units 620 c press edge parts of the LED card 1000 setbetween the arm parts 620 b, to prevent the LED card 1000 from beingdropped from the socket 6.

Between the lower member 61 and the upper member 62, springs 62 b areplaced around the hinge axis 62 a. As shown in FIG. 9, both ends of eachspring 62 b respectively hold both the lower member 61 and the uppermember 62. Due to this, pressures are normally (i.e., when the lock unit63 is at an unlocked position) applied to the upper member 62 toward anopen state. As shown in FIG. 9, a coil spring is suitable for use as thespring 62 b.

6-3. Effect of the Socket 6

According to the above-construction of the socket 6, the followingeffect can be produced.

The following describes the effect produced by the socket relating tothe sixth embodiment, based on the method for mounting the LED card 1000onto the socket 6.

As shown in FIG. 9, for the socket 6 where the upper member 62 is in anormal open state, i.e., where the arm parts 620 b of the upper member62 are lifted up, the user inserts the LED card 1000 between the armparts 620 b until the LED card 1000 reaches the base part 620 a. Due tothis user operation, the feeding terminals 1001 a to 1001 n of the LEDcard 1000 are electrically connected to the external terminals 622 a to622 n placed within the upper member 62.

After setting the LED card 1000 in this way, the user then sways downthe arm parts 620 b of the upper member 62 on the hinge axis 62 a, topress the upper member 62 against the lower member 61.

FIG. 10 shows a cross sectional view of the socket 6 in a state wherethe upper member 62 is pressed against the lower member 61. With thesocket 6 being in this state, the user moves the slide plate 630 in thearrow direction as indicated by a broken line in FIG. 10, to lock theedge part 1000 c of the LED card 1000. This completes the operation formounting the LED card 1000.

In this way, the LED card 1000 can be mounted on the socket 6 by simplyplacing the upper member into an open state and inserting the LED card1000 between the two arm parts 620 b in the sixth embodiment.Accordingly, the mounting and replacing operations of the LED card 1000can be remarkably simplified and the burden on the user can bedrastically alleviated, as compared with conventional cases.

Further, because the socket 6 bases its operation on the swinging motionas described above, the socket 6 can be embedded within the recessedpart of the case 2102 as shown in FIG. 8. By doing so, the lightingsystem 2500 can have a beautiful finish without any disfigurement.

The LED card 1000 mounted in this way has its side parts 1000 a and 1000b pressed against the lower member 61 by the elastic contact units 621and 620 c formed as blade springs. Therefore, the back surface of theLED card 1000 is pressed, in direct contact, against the heat-releasingsheet 613 placed on the lower member 61. Due to this, for the socket 6relating to the sixth embodiment, heat generated in the LED card 1000can be favorably conducted to the heat sink 2122 placed on the lowermember 61 via the heat-releasing sheet 613 and the lower member 61,thereby producing a high heat-releasing effect.

Here, it is preferable to set the pressure applied by the elasticcontact units 621, 620 c, and the external terminals 622 a to 622 n tothe LED card 1000 in such a range that does not damage the LED card 1000and allows the LED card 1000 to be mounted and removed favorably byhuman hands. To be specific, it is preferable to set the pressure in arange of 0.05 to 1.00 kg/cm² inclusive.

It is preferable to set the height of the slide plate 630 to besubstantially the same as the total of the height of the LED card 1000in its thickness direction and the height of the heat-releasing sheet613 in its thickness direction, or a little smaller than the total. Bysetting the height of the slide plate 630 in this way, the state wherethe slide plate 630 presses the LED card 1000 against the lower member61 can be maintained. Due to this, the back surface of the LED card 1000can be pressed, in direct contact, against the heat-releasing sheet 613without via air whose heat conductivity is extremely low. Therefore, theheat-releasing effect can be improved further.

It should be noted here that the LED card 1000 can be removed by theprocedure opposite to the above mounting procedure.

According to the sixth embodiment as described above, the upper member62 holding the LED card 1000 can be fixed with being pressed against thelower member 61 by the lock unit 63. Therefore, the effect can beproduced of efficiently releasing heat generated in the LED card 1000.

Further, the elastic contact units 621 and 620 c are formed integrallyas parts of the upper member 62, to reduce the number of components. Inthis way, another effect of reducing the manufacturing cost can beproduced.

7. SEVENTH EMBODIMENT

7-1. Construction of the Socket 7

FIG. 11 shows the construction of a socket 7 for an LED light sourcerelating to the seventh embodiment.

The socket 7 relating to the seventh embodiment is characterized by itsconstruction part including a lower member 71, which is different fromthat of the socket 6 relating to the sixth embodiment. The presentembodiment is described focusing on the different construction part.

As shown in the figure, the lower member 71 includes a lower member mainunit 710 that is a frame member in which a rectangular opening unit(base opening unit) 712 is formed. The size of the base opening unit 712is set substantially equal to or larger than the size of the LED card1000.

A lock unit 73 includes a pair of lock supporting parts 711, a hingeaxis 732, and a lock main part 730. The lock main part 730 is supportedby the lock supporting parts 711 on the hinge axis 732. The locksupporting parts 711 are rectangular parts formed by cutting thecorresponding parts of the lower member main unit 610 and bending thecut parts so as to be perpendicular to the main surface of the lowermember main unit 610. The two lock supporting parts 711 are positionedsymmetric to each other with a certain distance between them. Due tothis construction, the lock unit 73 bases its operation on the swingingmotion described below.

The lock main part 730 is formed by processing a rectangular metalplate. The lock main part 730 includes a base part 734, a lock lever733, and lock projections 731.

The base part 734 is a middle part of the lock main part 730. Both ends733 a and 733 b of the base part 734 are supported on the hinge axis 732in such a manner that the lock unit 73 can swing freely.

The lock lever 733 is formed by bending a top part of the lock main part730 to extend from the base part 734 in L-shape. The lock lever 733 hassuch a size that allows the user to easily operate with his or herfingers.

The lock projections 731 are formed by bending top parts of the lockmain part 730 to extend in L-shapes from both ends of the base part 734in the direction opposite to the direction where the lock lever 733extends. The lock projections 731 are formed to be directly engaged inlock catches 723 of the arm parts 720 b of the upper member 72 when thesocket 7 is in a closed state.

The lock main part 730 is positioned in such a manner that theengagement of the lock projections 731 and the lock catches 723 ispositioned substantially right above the hinge axis 732 as viewed in theside surface direction of the socket 7. By this positioning, even ifsome troubles occur and the closed upper member 72 is mistakenly pressedup, the lock main part 730 locks the upper member 72 without beingswayed by the force of such pressing-up. This positioning of the lockmain part 730 aims at realizing secure locking.

It is preferable to provide the lock main part 730 with spring membersequivalent to the springs 72 b shown in FIG. 11, so that the lock unit73 is pressed to sway in the bending direction of the lock protrusions731. By doing so, the above locking effect can be improved further. Onthe contrary, the lock unit.73 may be pressed to swing in the directionopposite to the bending direction of the lock projections 731. By doingso, the upper member 72 can be more easily placed in an open state whenthe lock lever 733 is operated by the user.

7-2. Effect of the Socket 7

The socket 7 having the above-described construction is first fixed to aheat sink (3000 or the like) using screw holes 710 a formed in the lowermember 71. Here, it is preferable to place a heat-releasing sheet(equivalent to 613) in the surface area of the heat sink that is exposedthrough the base opening unit 713 of the lower member 71.

To mount the LED card 1000 onto the socket 7, the user inserts the LEDcard 1000 in the grooves of the arm parts 720 b of the upper member 72and slides the LED card 1000 in the same manner as that described in thesixth embodiment.

As in the sixth embodiment, the elastic contact units 721 of the armparts 720 b press the edge parts of the LED card 1000 in the directionwhere the lower member 71 is positioned, and also, the LED card 1000 iselectrically connected via the external terminals 722 a to 722 n held bythe terminal holding member 722. Further, the light source unit 1002 ofthe LED card 1000 is exposed through the opening unit 700.

In this state, the user then sways down the upper member 72, and liftsthe lock lever 733 of the lock unit 73 toward the upper member 72 whilepressing the upper member 72 against the lower member 71. Due to this,the lock unit 73 sways on the hinge axis 732, and the lock projections731 are directly engaged in the lock catches 723 of the arm parts 720 bof the upper member 72.

With this operation, the LED card 1000 set in the upper member 72 is fitin the base opening unit 712 of the lower member 71. The back surface ofthe LED card 1000 then faces the heat sink placed right below the lowermember 71. Here, it is preferable to place a heat-releasing sheet on thesurface of the heat sink, so that heat generated in the LED card 1000can be released to the heat sink via the heat-releasing sheet. By doingso, a high heat-releasing effect can be produced. In the seventhembodiment, heat generated in the LED card 1000 can be released to theheat sink without making the LED card 1000 come in contact with thelower member 71. Therefore, a higher heat-releasing effect can beproduced in the seventh embodiment than in the sixth embodiment.

Here, even without the heat-releasing sheet, a certain degree ofheat-releasing effect can be produced because the LED card 1000 facesthe heat sink with an extremely narrow gap between them (a gapsubstantially corresponding to the thickness of the lower member 71). Itis however preferable to place the heat-releasing sheet, to obtain ahigher heat-releasing effect.

To remove the LED card 1000, the user presses down the lock lever 733,so that the lock unit 73 sways up and its lock projections 731 aredisengaged from the lock catches 723. With being unlocked, the uppermember 72 is lifted up, and placed in an open state. In this state, theuser can easily extract the LED card 1000.

According to the seventh embodiment as described above like in the sixthembodiment, the burden on the user replacing the LED card 1000 can bedrastically alleviated as compared with conventional cases.

In the seventh embodiment, the lower member 71 has the base opening unit713 formed therein. As compared with the sixth embodiment, therefore, amaterial used for the socket can be reduced by an amount correspondingto the base opening unit 713 in the seventh embodiment. The seventhembodiment is also advantageous in its low material cost.

By employing the socket 7 relating to the seventh embodiment for alighting system, the lighting system can have a beautiful finish as inthe sixth embodiment.

8. EIGHTH EMBODIMENT

8-1. Construction of the Socket 8

FIG. 12 shows the construction of the socket 8 for an LED light sourcerelating to the seventh embodiment.

For the sockets 6 and 7 relating to the sixth and seventh embodiments,the LED card 1000 is set in the grooves of the upper members 62 and 72.The socket 8 relating to the eighth embodiment differs from the sockets6 and 7 relating to the sixth and seventh embodiments in that the LEDcard 1000 is set on a lower member 8 1. The following describes thesocket 8, focusing on the construction part that is different from theconstructions of the sockets 6 and 7.

The lower member 81 includes a lower member main unit 810, upper membersupporting parts 812, and a lock unit 83. The lower member main unit 810is a metal plate formed by nickel-plating brass with high heatconductivity. The upper member supporting parts 812 support the uppermember 82.

Unlike in the case of the socket 7, the lower member main unit 810 isnot a frame member in which a base opening unit is formed, but is aplate member. Instead, an area (card placement area) 814 in which an LEDcard is to be set is provided on the main surface of the lower membermain unit 810. Also, a plurality of alignment projections 813 are formedon the main surface of the lower member main unit 810. The alignmentprojections 813 are formed by partially cutting the corresponding partsof the lower member main unit 810 and bending the cut parts so as to beperpendicular to the main surface of the lower member main unit 810.Further, a plurality of screw holes 810 a are formed in the lower membermain unit 810 to fix the lower member main unit 810 to a heat sink orthe like.

The lock unit 83 includes a lock main part 830, a lock projection 831,and arm parts 833, etc.

The lock main part 830 is formed by processing a belt-shaped member. Asshown in FIG. 12, both ends of the lock main part 830 in itslongitudinal direction are supported by a pair of lock supporting parts811 formed in the lower member main unit 810 in such a manner that thelock unit 83 can sway freely on a hinge axis 832.

The lock projection 831 is formed by bending a top part of the lock unit83 to extend from the lock main part 830 in the direction where the cardplacement area 814 is positioned. The lock projection 831 is bent atsuch an angle that enables the lock projection 831 to be directlyengaged in a lock catch 823 formed in the upper member 82.

The arm parts 833 are formed by cutting parts of the lock unit 83 intothin and long rectangular shapes to extend from both ends of the lockmain part 830, and bending the cut parts in the direction where the cardplacement area 814 is positioned. It is preferable to set an angle atwhich the arm parts 833 are bent with respect to the lock main part 830at 90° or larger. Notch parts 810 b corresponding to the arm parts 833are formed in the lower member main unit 810, so that the lock unit 83can sway freely without its arm parts 833 being blocked by the lowermember main unit 810.

On the other hand, the upper member 82 includes a rectangularframe-shaped main unit 820, and an external terminal unit 822.

The main unit 820 is formed by processing a plate member with highstrength such as a stainless steel plate. The main unit 820 is a framemember in which a rectangular opening unit 82 c is formed. Through theopening unit 82 c, the light source unit 1002 of the LED card 1000 isexposed. The external terminal unit 822 having substantially the sameconstruction as the external terminal units 622 and 722 is placed in thevicinity of one side of the rectangular opening unit 82 c. On this sideof the main unit 820, a hinge axis 82 a is positioned. On the remainingthree sides of the opening unit 82 c, elastic contact units 821 havingsubstantially the same construction as the elastic contact units 621 and721 are formed by cutting the corresponding parts of the main unit 820into T-shapes and bending the cut T-shaped parts inward.

The lock catch 823 is formed in the main unit 820 to face the lock unit83 of the lower member 81, so that the lock catch 823 can directlyengage therein the lock projection 831. The lock catch 823 is formed bycutting the corresponding part of the main unit 820 and bending the cutpart.

8-2. Effect of the Socket 8

The socket 8 having the above-described construction is fixed to thesurface of the heat sink (3000 or the like) using a plurality of screwholes 810 a.

In this state, the user first opens the upper member 82, and then placesthe LED card 1000 on the card placement area 814 of the lower member 81.Here, in the socket 8, the LED card 1000 can be accurately aligned bythe alignment projections 813 positioned to surround the card placementarea 814, without being shifted to wrong positions. According to theeighth embodiment, therefore, the LED card 1000 can be placedaccurately.

Further, the following effect can be produced in the eighth embodimentwhen the LED card 1000 is placed. FIGS. 13A to 13C show partial crosssections of the socket for explaining the effect.

As shown in FIG. 13A, the arm parts 833 formed at an angle of 90° orlarger with respect to the lock main part 830 are away from the lowermember main unit 810 in the upper direction when the LED card 1000 isnot mounted. Because the arm parts 833 are formed integrally as parts ofthe lock unit 83, the lock main part 830 and the lock projection 831 areaccordingly inclined outward.

Here, the lock unit 83 is pressed by springs (not shown) in such adirection that causes the tips of the arm parts 833 to be lifted up.

Then, the user inserts the LED card 1000 into the socket in such amanner that the LED card 1000 is surrounded by the alignment projections813. As shown in FIG. 13B, the base surface of the LED card 1000 comesin contact with the arm parts 833, pressing down the arm parts 833.Along with this motion of the arm parts 833, the lock main part 830 ispressed up, and the lock catch 823 is moved to cover the upper member82. The arm parts 833 are finally fit in the notch parts 810 b formed inthe lower member main unit 810, so that the arm parts 833 are parallelto the flat surface of the lower member main unit 810.

After this, the user presses down the lock projection 831 by fingers.With this user operation, the lock projection 831 is directly engaged inthe lock catch 823 of the upper member main unit 820, thereby the upperframe 82 is locked on the lower frame 81. Due to this, the LED card 1000is pressed against the lower member 81 by the elastic force produced bythe elastic contact units 821 of the upper member 82 shown in FIG. 12.Via the lower member main unit 810, heat generated in the LED card 1000can be favorably released to the heat sink. In the eighth embodiment,the lower member 81 is particularly made from a metal material with highheat conductivity, and the LED card 1000 comes in contact with the lowermember 81. Therefore, an extremely high heat-releasing effect can beproduced.

To remove the LED card 1000, the lock main part 830 is to be swayed inthe direction opposite to the above swaying, so that the arm parts 833are lifted up. Then, the LED card 1000 too is lifted up based on theprinciple of leverage. Accordingly, the user can easily remove the LEDcard 1000 from the socket 8 while being free from such a problem thatthe LED card 1000 may get stuck in the socket 8.

Further, because the LED card 1000 can be easily mounted on and removedfrom this socket 8, the burden on the user relating to the replacementoperation of the LED card 1000 can be drastically alleviated. Also, byemploying the socket 8 for a lighting system, the lighting system canhave good heat-releasing properties and good replacement operabilitywithout any disfigurement, as in the case of the sway-type sockets 6 and7 relating to the sixth and seventh embodiments.

9. NINTH EMBODIMENT 9-1. Construction of the Socket 9

FIG. 14 is a perspective view of a socket 9 for an LED light sourcerelating to a ninth embodiment of the present invention.

The socket 9 is the same as the socket 8 relating to the eighthembodiment in that a lower member 91 has alignment projections 913 foraligning the LED card 1000. The socket differs from the socket 8 in thata base opening unit 914 corresponding to the size of the LED card 1000is formed in the lower member 91 instead of the card placement area 814.Also, the socket 9 is characterized in that a lock unit 93 is providednot on the lower member 91 but on an upper member 92.

To be more specific, the lower member 91 includes a lower member mainunit 910 formed by processing a metal plate into a rectangular frameshape. The lower member main unit 910 has, in the vicinity of therectangular base opening unit 914 formed therein, a pair of upper membersupporting parts 912, a plurality of alignment projections 913, and aplurality of lock catches 931, which are formed by cutting and bendingthe corresponding parts of the lower member main unit 910. Referencenumeral 92 a in FIG. 14 represents a hinge axis, which is the same asthe hinge axis described in the above embodiments, provided in each ofthe upper member supporting parts 912. In the lock catches 931,rectangular holes in which lock projections can be fit are formed.

The upper member 92 has a rectangular opening unit 92 c through whichthe light source unit 1002 of the LED card 1000 is exposed, an externalterminal unit 922, and the lock unit 93. At the upper member supportingparts 912, the upper member 92 and the lower member 91 are combinedtogether on the hinge axis 92 a.

The lock unit 93 includes a lock lever 930, the lock projections 923,and a hinge axis 933. The lock unit 93 is positioned to face theexternal terminal unit 922 placed in the vicinity of the rectangularopening unit 92 c formed in the upper member main unit 920.

The lock lever 930 and the lock projections 923 are formed by cuttingand bending the corresponding parts of one metal plate. The lock lever930 may be formed, for example, as a flat rectangular plate. The twolock projections 923 may be formed to extend like arms from both ends ofthe lock lever 930 by bending the corresponding parts at right angles.

At the tips of the lock projections 923, lock hooks 9231 to be engagedin the lock catches 931 are formed.

The lock lever 930 with the lock projections 923 is supported on thehinge axis 933 provided at inner both ends of the opening unit 92 c ofthe upper member 92 in such a manner that the lock lever 930 can freelysway. Here, the lock lever 930 is positioned to externally extend fromthe upper member main unit 922. The lock projections 923 are positionedat the inner side of the upper member main unit 922. It should be notedhere that the hinge axis 933 has a coil spring (not shown) that normallyapplies pressures in such a direction that causes the lock lever 930 tobe lifted up.

9-2. Effect of the Socket 9

The socket 9 having the above-described construction is fixed to theheat sink using screw holes 910 a.

To mount the LED card 1000, the user first opens the upper member 92 bylifting it up, and then places the LED card 1000 to be aligned with thebase opening unit 914 of the lower member 91. Here, as in the case ofthe socket 8, the LED card 1000 can be accurately aligned on the lowermember 91 of the socket 9 by the alignment projections 913. The LED card1000 can be accurately aligned by the alignment projections 913 withoutbeing shifted to wrong positions.

Following this, the user closes the upper member 92 by pressing the locklever 930 of the lock unit 93. While maintaining the closed state, theuser releases the pressing of the lock lever 930. Due to this, the locklever 930 is lifted up by the force of the coil spring, and the lockhooks 9231 at the tips of the lock projections 923 are directly engagedin the lock catches 931 of the lower member 71. It should be noted herethat the upper member 92 can also be manually lifted up easily withoutusing the coil spring.

With this construction, the socket 9 relating to the ninth embodimentcan produce substantially the same effect as the effect produced by thesocket 8 relating to the eighth embodiment. Further, the ninthembodiment is characterized in that the base opening unit 914 is formedin the lower member main unit 910. Therefore, the LED card 1000 can beaccurately aligned by the alignment projections 913 and heat generatedin the LED card 1000 can be directly released to the heat sink placed onthe lower member 71. Therefore, a relatively high heat-releasing effectcan be produced.

To remove the LED card 1000, the user presses the lock lever 930 so thatthe lock unit 93 sways and the lock projections 923 are easilydisengaged from the lock catches 931. Due to this, the upper member 92is lifted up, and the LED card 1000 can be removed. In this way, thereplacement operability of the LED card 1000 for the user can also beimproved.

Also, by employing the socket 9 for a lighting system, the lightingsystem can have good heat-releasing properties and good replacementoperability without any disfigurement as in the sixth and eighthembodiments.

10. Additional Matters

Although the above embodiments describe the case where the LED card 1000is formed by integrating an 8 by 8 matrix of 64 LED elements, thepresent invention should not be limited to this card construction. TheLED card 1000 may have other card constructions such that a 5 by 5matrix of 25 LED elements are integrated.

Further, the dimensions of the LED card and the socket should not belimited to those described in the above embodiments, but maybe changedappropriately. The thickness of the LED card should not be limited to1.2 mm employed in the above embodiments, but may be for example in arange of 1.0 to 1.5 mm.

Also, the present invention is expected to produce a high effect whenthe back surface of the LED card is flat and can easily come in contactwith the heat sink. Such an LED card whose back surface is flat is oftenconstructed by using bare chips. However, the present invention shouldnot be limited to the LED card using bare chips but can be applied toLED cards using other types of LED elements (e.g., surface mount devicetype). In the case of the LED cards using the other types of LEDelements, too, a certain level of effect can be produced.

Further, the above embodiments describe the case where the LED card 1000having the metal layer 1031 is used. This construction is preferable toimprove the mechanical strength of the LED card 1000 for the purpose ofmaking the back surface of the LED card 1000 come in contact with theheat sink 3000 when, as one example, the elastic pressing units 14R,14L, and 14C at the edge vicinities of the opening unit 1000 press theedges of the light source unit 1002 in the socket 1 relating to thefirst embodiment.

The metal layer 1031 may not be included in the LED card to be set inthe socket etc., of the present invention. It is however preferable toemploy the metal layer 1031, to obtain favorable heat-releasingproperties and mechanical strength of the LED card 1000.

It is preferable that the entire back surface of the LED card comes incontact with the heat sink or with the lower member. However, a certainlevel of effect can be produced even when the back surface of the LEDcard only partially comes in contact with the heat sink or with thelower member.

Further, it is preferable that the LED light-source socket described inthe above embodiments includes a detector for detecting the setting ofthe LED card 1000. The detector is pressed by the LED card 1000 when theLED card 1000 is set in the socket. Only when the detector detects thesetting of the LED card 1000, power is supplied from the externalterminals to the LED card 1000. With the use of such a detector, theuser can replace the LED card 1000 safely, without worrying abouttouching the external terminals during the replacement operation.

Alternatively, recessions may be formed in parts of the LED card 1000other than the parts corresponding to the light source unit 1002 and thefeeding terminals 1001 a to 1001 n. By doing so, the setting of the LEDcard 1000 can be detected by the tactile feedback sensed when theelastic pressing members of the socket are fit into the recessions.

Further, notches may be formed in the corners of the LED card 1000, andprojections corresponding to the notches may be formed in the socket, toprevent erroneous insertion of the LED card 1000.

Moreover, the lock unit described in the sixth to ninth embodiments maybe provided in either the upper member or the lower member as long asthe upper member and the lower member can be locked via the lock unit.

INDUSTRIAL APPLICATION

The present invention is applicable to lighting apparatuses and lightingsystems that are required to have a feature of being compact, thin,lightweight or the like.

1. A socket that holds a card-type LED module and is fixed to a heatsink, the LED module having a light source unit on a main surfacethereof, the light source unit being formed by integrated LED elements,the socket comprising a frame structure that holds the LED module in astate where the light source unit is exposed through an opening of theframe structure, and that presses, at a position close to the opening,the LED module to enable a back surface of the LED module to be pressedagainst a surface of the heat sink.
 2. The socket of claim 1, whereinthe frame structure includes a pressing member that has elasticity andis at such a position facing the LED module on a back surface of theframe structure.
 3. The socket of claim 2, wherein the frame structurehas a slot area through which the LED module is removably insertedtherein, and a cutout area that is formed to spatially connect the slotarea and the opening, for guiding the light source unit to the openingwhen the LED module is inserted.
 4. The socket of claim 2, wherein thepressing member is formed integrally as a part of the frame structure.5. The socket of claim 1, wherein the frame structure is made of brassor stainless steel.
 6. The socket of claim 1, wherein the framestructure includes a lower frame-part and an upper frame-part, the lowerframe-part coming in contact with the heat sink, the upper frame-partbeing a frame for holding the LED module and being fixed to the lowerframe-part, and includes a pressing member that has elasticity and isprovided on the upper frame-part, and the pressing member presses theLED module against a surface of the lower frame-part, and the lowerframe-part is fixed in contact with the surface of the heat sink.
 7. Thesocket of claim 6, wherein the lower frame-part and the upper frame-partare made of brass or stainless steel.
 8. The socket of claim 1, whereina pressure applied by at least the pressing member to the LED module isin a range of 0.05 to 1.00 kg/cm² inclusive.
 9. The socket of claim 1,wherein a feeding terminal is provided at a position facing the LEDmodule on the frame structure, the feeding terminal includes a pluralityof contacts made of phosphor bronze, and an elastic force of thecontacts presses the LED module against the heat sink.
 10. The socket ofclaim 1, wherein the socket is fixed to the heat sink via a screw.
 11. Alighting system comprising: the socket of claim 1; a card-type LEDmodule set in the socket; and a heat sink.
 12. A socket that holds acard-type LED module and is fixed to a heat sink, the LED module havinga light source unit on a main surface thereof, the LED module beingformed by integrated LED elements, the socket including a framestructure including a lower frame-part and an upper frame-part, thelower frame-part being placed on the heat sink, the upper frame-partbeing a frame holding the LED module in a state where the light sourceunit is exposed through an opening of the frame, wherein the upperframe-part is supported by the lower frame-part via a hinge in such amanner that the upper frame-part can be open and closed, the upperframe-part includes a pressing unit for pressing the LED module againstthe lower frame-part, and the lower frame-part includes, in a main partthereof, a lock unit for directly or indirectly locking the upperframe-part when the upper frame-part is closed.
 13. The socket of claim12, wherein the upper frame-part includes a base part and a pair of armparts, the base part being supported on an axis in an area where theupper frame-part is supported by the lower frame-part, the pair of armparts respectively extending from both ends of the base part, the armparts have grooves formed at facing positions thereof, for guiding edgeparts of the LED module in a longitudinal direction of the arm parts,and the pressing unit of the upper frame-part is formed within thegrooves to press the edge parts of the LED module against the lowerframe-part in a state where the LED module is held in the grooves. 14.The socket of claim 12, wherein a heat-releasing sheet is provided on asurface of the main part of the lower frame-part facing the LED module.15. The socket of claim 12, wherein an opening is formed in the mainpart of the lower frame-part for enabling a base surface of the LEDmodule to face the heat sink.
 16. The socket of claim 13, wherein thelock unit in the main part of the lower frame-part has a slide partplaced to be slidable in a longitudinal direction of the arm parts whenthe upper frame-part is closed, and the slide part locks edges of theLED module held by the arm parts when the upper frame-part is closed,thereby the upper frame-part is indirectly locked.
 17. The socket ofclaim 12, wherein the lock unit is supported on an axis in a freelyswayable manner, at a position opposite to a position of the hingebetween the lower frame-part and the upper frame-part, and the lock unitsways toward the upper frame-part when the upper frame-part is closed,thereby the upper frame-part is directly locked on the lower frame-part.18. The socket of claim 17, wherein an area of locking between the lockunit and the upper frame-part is positioned right above the axis onwhich the lock unit is supported in a freely swayable manner.
 19. Thesocket of claim 12, wherein the lower frame-part has, in the main part,a projection for aligning the LED module.
 20. The socket of claim 17,wherein the lower frame-part has, in the main part, a plurality ofprojections for aligning the LED module, the projections beingpositioned so as to surround the LED module, and a base opening isformed in an area surrounded by the projections, for enabling a basesurface of the LED module to face the heat sink.
 21. The socket of claim12, wherein the pressing unit is formed integrally as a part of theupper frame-part by processing the part of the upper frame-part.
 22. Alighting system comprising: the socket of claim 12; and a case forfixing the socket.